diff options
Diffstat (limited to 'sys/include/arch/amd64/bus.h')
-rw-r--r-- | sys/include/arch/amd64/bus.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/sys/include/arch/amd64/bus.h b/sys/include/arch/amd64/bus.h index 8f9bc39..b9d3362 100644 --- a/sys/include/arch/amd64/bus.h +++ b/sys/include/arch/amd64/bus.h @@ -32,6 +32,14 @@ #include <sys/types.h> +/* + * Hyra assumes that the bootloader uses PDE[256] for some + * higher half mappings. To avoid conflicts with those mappings, + * this offset is used to start device memory at PDE[257]. This + * will give us more than enough space. + */ +#define MMIO_OFFSET (VM_HIGHER_HALF + 0x8000000000) + typedef uint64_t bus_addr_t; int bus_map(bus_addr_t addr, size_t size, int flags, void **vap); |